DAMAGE-SENSING COMPOSITE STRUCTURES
A composite includes a matrix material and a unidirectional array of carbon nanotube-infused fibers disposed in a portion of the matrix material. An article includes this composite and a network of electrodes disposed about the periphery of the composite. The electrodes send and receive an electrical charge. Such an article is included in a system, along with sensing circuitry and a source for supplying current to the network of electrodes. Such a system is used in a method that includes subjecting the article to a load that causes a condition in the composite including strain, fatigue, damage, or cracks, and monitoring the location of the condition.
1 . A composite comprising:
a) a matrix material; and
b) a first unidirectional array of carbon nanotube (CNT)-infused fibers disposed in at least a portion of said matrix material.
2 . The composite of claim 1 , wherein the matrix material is selected from a thermoset, a thermoplastic, a ceramic, and a cement.
3 . The composite of claim 1 , wherein the infused CNTs are selected from multi-walled CNTs, double-walled CNTs, single-walled CNTs; and mixtures thereof.
4 . The composite of claim 3 , wherein the infused CNTs are multi-walled CNTs.
5 . The composite of claim 1 , wherein the infused CNTs are aligned substantially along the fiber axis.
6 . The composite of claim 1 , wherein the infused CNTs are aligned substantially perpendicular to the fiber axis.
7 . The composite of claim 1 , wherein the infused CNTs are present in a range from between about 0.01 percent to about 1 percent by weight of the composite.
8 . The composite of claim 1 , wherein the infused CNTs range in length from between about 100 nanometers to about 5 microns.
9 . The composite of claim 1 , wherein the CNT-infused fibers are selected from glass fibers, aramid fibers, ceramic fibers, and mixtures thereof.
10 . The composite of claim 1 , wherein said first unidirectional array of CNT-infused fibers comprises a continuous fiber.
11 . The composite of claim 1 , wherein said first unidirectional array of CNT-infused fibers comprises a plurality of discontinuous fibers.
12 . The composite of claim 1 , wherein said first unidirectional array of CNT-infused fibers is disposed at the surface of the composite.
13 . The composite of claim 1 , further comprising a second unidirectional array of CNT-infused fibers.
14 . The composite of claim 13 , wherein said second unidirectional array of CNT-infused fibers is disposed at an angle from between about 0 degrees to about 90 degrees, relative to said first unidirectional array of CNT-infused fibers.
15 . The composite of claim 13 , further comprising an insulating layer disposed between said first unidirectional array of CNT-infused fibers and said second unidirectional array of CNT-infused fibers.
16 . An article comprising:
a) a composite comprising:
i) a matrix material; and
ii) a first unidirectional array of carbon nanotube (CNT)-infused fibers disposed in at least a portion of said matrix material; and
b) a network of electrodes disposed about the periphery of said composite for sending and receiving an electrical charge.
17 . The article of claim 16 , further comprising sensing circuitry connected to the network of electrodes for detecting a change in resistance across the composite.
18 . The article of claim 17 , wherein the sensing circuitry is capable of measuring and mapping the location of strain, fatigue, damage, and/or cracks in said composite.
19 . The article of claim 16 , wherein the matrix material is selected from a thermoset, a thermoplastic, a ceramic, and a cement.
20 . The article of claim 16 , wherein CNTs of the CNT-infused fibers are, selected from multi-walled CNTs, double-walled CNTs, single-walled CNTs; and mixtures thereof.
21 . The article of claim 20 , wherein the infused CNTs are multi-walled CNTs.
22 . The article of claim 16 , wherein the infused CNTs are aligned substantially along the fiber axis.
23 . The article of claim 16 , wherein the infused CNTs are aligned substantially perpendicular to the fiber axis.
24 . The article of claim 16 , wherein the infused CNTs are present in a range from between about 0.01 percent to about 1 percent by weight of the composite.
25 . The article of claim 16 , wherein the infused CNTs range in length from between about 100 nanometers to about 5 microns.
26 . The article of claim 16 , wherein the CNT-infused fibers are selected from glass fibers, aramid fibers, ceramic fibers, and mixtures thereof.
27 . The article of claim 16 , wherein said first unidirectional array of CNT-infused fibers comprises a continuous fiber.
28 . The article of claim 16 , wherein said first unidirectional array of CNT-infused fibers comprises a plurality of discontinuous fibers.
29 . The article of claim 16 , wherein said first unidirectional array of CNT-infused fibers is disposed at the surface of the composite.
30 . The article of claim 16 , further comprising a second unidirectional array of CNT-infused fibers.
31 . The article of claim 30 , wherein said second unidirectional array of CNT-infused fibers is disposed at an angle from between about 0 degrees to about 90 degrees, relative to said first unidirectional array of CNT-infused fibers.
32 . The article of claim 30 , further comprising an insulating layer disposed between said first unidirectional array of CNT-infused fibers and said second unidirectional array of CNT-infused fibers.
33 . The article of claim 16 , wherein said a network of electrodes comprises a network of transmitting and receiving electrodes fabricated with silver paint.
34 . The article of claim 16 , wherein said a network of electrodes comprises a network of transmitting and receiving electrodes comprising embedded copper pins.
35 . A system comprising:
A) an article, said article comprising:
i) a composite, said composite comprising:
a) a matrix material; and
b) a first unidirectional array of carbon nanotube (CNT)-infused fibers disposed in at least a portion of said matrix material; and
B) sensing circuitry connected to the composite for detecting a change in resistance across the composite.
36 - 79 . (canceled)
80 . The system of claim 35 , further comprising a network of electrodes connecting said composite to said sensing circuitry.
81 . The system of claim 80 , further comprising a source for supplying current to said network of electrodes.
82 . The system of claim 35 , wherein the sensing circuitry is capable of measuring and mapping the location of strain, fatigue, damage, and/or cracks in said composite.
83 . The system of claim 35 , further comprising a computer equipped to receive resistance data from said sensing circuitry, said computer provided with software having a damage sensing algorithm.
84 . The system of claim 83 , further comprising a graphical user interface displaying the location of strain, fatigue, damage, and cracks in said composite.
85 . The system of claim 35 , wherein the matrix material is selected from a thermoset, a thermoplastic, a ceramic, and a cement.
86 . The system of claim 35 , wherein CNTs of the CNT-infused fibers are selected from multi-walled CNTs, double-walled CNTs, single-walled CNTs; and mixtures thereof.
87 . The system of claim 86 , wherein the infused CNTs are multi-walled CNTs.
88 . The system of claim 35 , wherein the infused CNTs are aligned substantially along the fiber axis.
89 . The system of claim 35 , wherein the infused CNTs are aligned substantially perpendicular to the fiber axis.
90 . The system of claim 35 , wherein the infused CNTs are present in a range from between about 0.01 percent to about 1 percent by weight of the composite.
91 . The system of claim 35 , wherein the infused CNTs range in length from between about 100 nanometers to about 5 microns.
92 . The system of claim 35 , wherein the CNT-infused fibers are selected from glass fibers, aramid fibers, ceramic fibers, and mixtures thereof.
93 . The system of claim 35 , wherein said first unidirectional array of CNT-infused fibers comprises a continuous fiber.
94 . The system of claim 35 , wherein said first unidirectional array of CNT-infused fibers comprises a plurality of discontinuous fibers.
95 . The system of claim 35 , wherein said first unidirectional array of CNT-infused fibers is disposed at the surface of the composite.
96 . The system of claim 35 , further comprising a second unidirectional array of CNT-infused fibers.
97 . The system of claim 96 , wherein said second unidirectional array of CNT-infused fibers is disposed at an angle from between about 0 degrees to about 90 degrees, relative to said first unidirectional array of CNT-infused fibers.
98 . The system of claim 96 , further comprising an insulating layer disposed between said first unidirectional array of CNT-infused fibers and said second unidirectional array of CNT-infused fibers.
99 . The system of claim 35 , wherein said network of transmitting and receiving electrodes comprises electrodes fabricated with silver paint.
100 . The system of claim 35 , wherein said network of transmitting and receiving electrodes comprises embedded copper pin electrodes.
101 . A method comprising:
1) providing a system; said system comprising:
A) an article, said article comprising:
a composite, said composite comprising:
a) a matrix material; and
b) a first unidirectional array of carbon nanotube (CNT)-infused fibers disposed in at least a portion of said matrix material; and
B) sensing circuitry connected to the composite for detecting a change in resistance across the composite; and
2) supplying a current to the composite allowing the sensing circuitry to detect a change in resistance which relates to a flaw or defect in the composite.
102 . The method of claim 101 , further comprising means for determining a location of said flaw or defect in the composite based on an output of the sensing circuitry.
103 . The method of claim 101 , wherein said flaw or defect is selected from strain, fatigue, damage, and/or cracks in said composite.
104 . The method of claim 101 , wherein the system further comprises a computer equipped to receive resistance data from said sensing circuitry, said computer provided with software having a damage sensing algorithm.
105 . The method of claim 104 , further comprising a graphical user interface displaying the location of strain, fatigue, damage, and cracks in said composite.
106 . The method of claim 101 , wherein the matrix material is selected from a thermoset, a thermoplastic, a ceramic, and a cement.
107 . The method of claim 101 , wherein CNTs of the CNT-infused fibers are selected from multi-walled CNTs, double-walled CNTs, single-walled CNTs; and mixtures thereof.
108 . The method of claim 107 , wherein the infused CNTs are multi-walled CNTs.
109 . The method of claim 101 , wherein the infused CNTs are aligned substantially along the fiber axis.
110 . The method of claim 101 , wherein the infused CNTs are aligned substantially perpendicular to the fiber axis.
111 . The method of claim 101 , wherein the infused CNTs are present in a range from between about 0.01 percent to about 1 percent by weight of the composite.
112 . The method of claim 101 , wherein the infused CNTs range in length from between about 100 nanometers to about 5 microns.
113 . The method of claim 101 , wherein the CNT-infused fibers are selected from glass fibers, aramid fibers, ceramic fibers, and mixtures thereof.
114 . The method of claim 101 , wherein said first unidirectional array of CNT-infused fibers comprises a continuous fiber.
115 . The method of claim 101 , wherein said first unidirectional array of CNT-infused fibers comprises a plurality of discontinuous fibers.
116 . The method of claim 101 , wherein said first unidirectional array of CNT-infused fibers is disposed at the surface of the composite.
117 . The method of claim 101 , further comprising a second unidirectional array of CNT-infused fibers.
118 . The method of claim 117 , wherein said second unidirectional array of CNT-infused fibers is disposed at an angle from between about 0 degrees to about 90 degrees, relative to said first unidirectional array of CNT-infused fibers.
119 . The method of claim 117 , further comprising an insulating layer disposed between said first unidirectional array of CNT-infused fibers and said second unidirectional array of CNT-infused fibers.
120 . The method of claim 101 , further wherein the system further comprises a network of transmitting and receiving electrodes.
121 . The method of claim 120 , wherein said network of transmitting and receiving electrodes comprises electrodes fabricated with silver paint.
122 . The method of claim 120 , wherein said network of transmitting and receiving electrodes comprises embedded copper pin electrodes.